2MASX J10222849+5006200

Lore & Background

2MASX J10222849+5006200 is classified as a low-excitation radio galaxy with a 1.4 GHz luminosity range between 2 × 10^23 and 3 × 10^25 W Hz⁻¹. It possesses an ellipsoidal stellar halo measuring about 80 kpc, with two diffuse ultra-steep spectrum radio sources extending roughly 100 kpc around the galaxy. In August 2022, Indian astronomers from Savitribai Phule Pune University, led by Surajit Paul, observed a burst of radio jet activity from its central black hole. They identified a first pair of radio lobes, described as the oldest such lobes the astronomers had seen, and detected diffuse radio structures formed 260 million years ago and 1.2 million years in length using the Giant Meterwave Radio Telescope.

Reader's Guide

The significance of 2MASX J10222849+5006200 lies in its classification as a 'Detached-Double-Double Radio Galaxy' (dDDRG) system. Following the primary pair of radio lobes, a team led by Gopal-Krishna found that the galaxy had drifted 250,000 light-years from its original position within the cluster's central region. During this drift, the galaxy erupted again in a new active phase, creating a younger set of radio lobes. Because both the old and young radio lobes lost their collinearity when the parent galaxy moved, the resulting structure became a dDDRG. This makes the galaxy a rare and valuable laboratory for studying radio jet activity, galaxy motion within clusters, and the evolution of radio lobes over hundreds of millions of years. The discovery of the oldest known radio lobes and the subsequent detection of younger lobes from the same galaxy highlight its unique role in understanding active galactic nuclei and cluster dynamics.

Did You Know?

• It is the brightest cluster galaxy (BCG) in the galaxy cluster Abell 980.
• Indian astronomers led by Surajit Paul discovered the oldest known pair of radio lobes from this galaxy in August 2022.
• The galaxy has drifted 250,000 light-years from its original position in the cluster center, creating a detached-double-double radio galaxy system.